pyLoad: Session Cookie Security Downgrade via Untrusted X-Forwarded-Proto Header Spoofing (Global State Race Condition)
pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev98, the set_session_cookie_secure before_request handler in src/pyload/webui/app/__init__.py reads the X-Forwarded-Proto header from any HTTP request without validating that the request originates from a trusted proxy, then mutates the global Flask configuration SESSION_COOKIE_SECURE on every request. Because pyLoad uses the multi-threaded Cheroot WSGI server (request_queue_size=512), this creates a race condition where an attacker's request can influence the Secure flag on other users' session cookies — either downgrading cookie security behind a TLS pro
pyLoad's Session Not Invalidated After Permission Changes
### Summary
The `pyload` application does not properly invalidate or modify sessions upon changes made to a user's permissions.
### Details
Whenever an administrator changes the permissions a specific account has, they do not expect that account still being able to access data that their new permissions do not allow. This is not the case for the `pyload` application, as a user with a valid session can still perform the actions.
### PoC
Take a user with all the permissions, as shown below.
We now log in as this user.
 function in src/pyload/plugins/extractors/UnTar.py uses os.path.commonprefix() for its path traversal check, which performs character-level string comparison rather than path-level comparison. This allows a specially crafted tar archive to write files outside the intended extraction directory. The correct function os.path.commonpath() was added to the codebase in the CVE-2026-32808 fix (commit 5f4f0fa) but was never applied to _safe_extractall(), making this an incomplete fix. This vulnerability is fixed in 0.5.0b3.dev97.
Authorization Bypass for SSL Certificate/Key Configuration Due to Option Name Mismatch in pyload-ng
pyLoad is a free and open-source download manager written in Python. Prior to 0.5.0b3.dev97, the ADMIN_ONLY_CORE_OPTIONS authorization set in set_config_value() uses incorrect option names ssl_cert and ssl_key, while the actual configuration option names are ssl_certfile and ssl_keyfile. This name mismatch causes the admin-only check to always evaluate to False, allowing any user with SETTINGS permission to overwrite the SSL certificate and key file paths. Additionally, the ssl_certchain option was never added to the admin-only set at all. This vulnerability is fixed in 0.5.0b3.dev97.
Высокий · CVSS 7.5EPSS 0,53%Нет опубликованного исправления
pyLoad has an incomplete fix for CVE-2026-33509: unprotected storage_folder enables arbitrary file write to Flask session store and code execution
pyLoad is a free and open-source download manager written in Python. The fix for CVE-2026-33509 added an ADMIN_ONLY_OPTIONS set to block non-admin users from modifying security-critical config options. The storage_folder option is not in this set and passes the existing path restriction because the Flask session directory is outside both PKGDIR and userdir. A user with SETTINGS and ADD permissions can redirect downloads to the Flask filesystem session store, plant a malicious pickle payload as a predictable session file, and trigger arbitrary code execution when any HTTP request arrives with the corresponding session cookie. This vulnerabilit
pyLoad has Improper Neutralization of Special Elements used in an OS Command
pyLoad is a free and open-source download manager written in Python. In 0.5.0b3.dev96 and earlier, the ADMIN_ONLY_OPTIONS protection mechanism restricts security-critical configuration values (reconnect scripts, SSL certs, proxy credentials) to admin-only access. However, this protection is only applied to core config options, not to plugin config options. The AntiVirus plugin stores an executable path (avfile) in its config, which is passed directly to subprocess.Popen(). A non-admin user with SETTINGS permission can change this path to achieve remote code execution.
pyLoad is a free and open-source download manager written in Python. In 0.5.0b3.dev96 and earlier, pyLoad has a server-side request forgery (SSRF) vulnerability. The fix for CVE-2026-33992 added IP validation to BaseDownloader.download() that checks the hostname of the initial download URL. However, pycurl is configured with FOLLOWLOCATION=1 and MAXREDIRS=10, causing it to automatically follow HTTP redirects. Redirect targets are never validated against the SSRF filter. An authenticated user with ADD permission can bypass the SSRF fix by submitting a URL that redirects to an internal address.
Высокий · CVSS 7.7EPSS 0,27%Нет опубликованного исправления
pyLoad has SSRF in parse_urls API endpoint via unvalidated URL parameter
pyLoad is a free and open-source download manager written in Python. In 0.5.0b3.dev96 and earlier, the parse_urls API function in src/pyload/core/api/__init__.py fetches arbitrary URLs server-side via get_url(url) (pycurl) without any URL validation, protocol restriction, or IP blacklist. An authenticated user with ADD permission can make HTTP/HTTPS requests to internal network resources and cloud metadata endpoints, read local files via file:// protocol (pycurl reads the file server-side), interact with internal services via gopher:// and dict:// protocols, and enumerate file existence via error-based oracle (error 37 vs empty response).
pyLoad: Server-Side Request Forgery via Download Link Submission Enables Cloud Metadata Exfiltration
pyLoad is a free and open-source download manager written in Python. Prior to version 0.5.0b3.dev97, PyLoad's download engine accepts arbitrary URLs without validation, enabling Server-Side Request Forgery (SSRF) attacks. An authenticated attacker can exploit this to access internal network services and exfiltrate cloud provider metadata. On DigitalOcean droplets, this exposes sensitive infrastructure data including droplet ID, network configuration, region, authentication keys, and SSH keys configured in user-data/cloud-init. Version 0.5.0b3.dev97 contains a patch.
Высокий · CVSS 7.5EPSS 0,55%Нет опубликованного исправления
pyload-ng: SETTINGS Permission Users Can Achieve Remote Code Execution via Unrestricted Reconnect Script Configuration
pyLoad is a free and open-source download manager written in Python. From version 0.4.0 to before version 0.5.0b3.dev97, the set_config_value() API endpoint allows users with the non-admin SETTINGS permission to modify any configuration option without restriction. The reconnect.script config option controls a file path that is passed directly to subprocess.run() in the thread manager's reconnect logic. A SETTINGS user can set this to any executable file on the system, achieving Remote Code Execution. The only validation in set_config_value() is a hardcoded check for general.storage_folder — all other security-critical settings including recon
pyload-ng: Improper Authentication and Origin Validation Error
pyLoad is a free and open-source download manager written in Python. Prior to version 0.5.0b3.dev97, a Host Header Spoofing vulnerability in the @local_check decorator allows unauthenticated external attackers to bypass local-only restrictions. This grants access to the Click'N'Load API endpoints, enabling attackers to remotely queue arbitrary downloads, leading to Server-Side Request Forgery (SSRF) and Denial of Service (DoS). This issue has been patched in version 0.5.0b3.dev97.
pyLoad: Arbitrary File Write via Path Traversal in edit_package()
pyLoad is a free and open-source download manager written in Python. From version 0.5.0b3.dev13 to 0.5.0b3.dev96, the edit_package() function implements insufficient sanitization for the pack_folder parameter. The current protection relies on a single-pass string replacement of "../", which can be bypassed using crafted recursive traversal sequences. This issue has been patched in version 0.5.0b3.dev97.
pyLoad CNL and captcha handlers allow code Injection via unsanitized parameters
pyLoad is a free and open-source download manager written in Python. In versions prior to 0.5.0b3.dev91, pyLoad web interface contained insufficient input validation in both the Captcha script endpoint and the Click'N'Load (CNL) Blueprint. This flaw allowed untrusted user input to be processed unsafely, which could be exploited by an attacker to inject arbitrary content into the web UI or manipulate request handling. The vulnerability could lead to client-side code execution (XSS) or other unintended behaviors when a malicious payload is submitted. user-supplied parameters from HTTP requests were not adequately validated or sanitized before b
Denial-of-Service attack in pyLoad CNL Blueprint using dukpy.evaljs
pyLoad is the free and open-source Download Manager written in pure Python. The jk parameter is received in pyLoad CNL Blueprint. Due to the lack of jk parameter verification, the jk parameter input by the user is directly determined as dykpy.evaljs(), resulting in the server CPU being fully occupied and the web-ui becoming unresponsive. This vulnerability is fixed in 0.5.0b3.dev92.
PyLoad vulnerable to SQL Injection via API /json/add_package in add_links parameter
pyLoad is the free and open-source Download Manager written in pure Python. Prior to version 0.5.0b3.dev91, the parameter add_links in API /json/add_package is vulnerable to SQL Injection. Attackers can modify or delete data in the database, causing data errors or loss. This issue has been patched in version 0.5.0b3.dev91.
pyLoad CNL Blueprint is vulnerable to Path Traversal through `dlc_path` leading to Remote Code Execution (RCE)
pyLoad is the free and open-source Download Manager written in pure Python. In versions 0.5.0b3.dev89 and below, there is an opportunity for path traversal in pyLoad-ng CNL Blueprint via package parameter, allowing Arbitrary File Write which leads to Remote Code Execution (RCE). The addcrypted endpoint in pyload-ng suffers from an unsafe path construction vulnerability, allowing unauthenticated attackers to write arbitrary files outside the designated storage directory. This can be abused to overwrite critical system files, including cron jobs and systemd services, leading to privilege escalation and remote code execution as root. This issue
Pyload log Injection via API /json/add_package in add_name parameter
### Summary
A log injection vulnerability was identified in `pyload` in API `/json/add_package`. This vulnerability allows user with add packages permission to inject arbitrary messages into the logs gathered by `pyload`.
### Details
`pyload` will generate a log entry when creating new package using API `/json/add_package`. This entry will be in the form of `Added package 'NAME_OF_PACKAGE' containing 'NUMBER_OF_LINKS' links`. However, when supplied with the name of new package containing a newline, this newline is not properly escaped. Newlines are also the delimiter between log entries. This allows the attacker to inject new log entries into
pyLoad has Path Traversal Vulnerability in json/upload Endpoint that allows Arbitrary File Write
pyLoad is a free and open-source Download Manager written in pure Python. In version 0.5.0b3.dev89, an authenticated path traversal vulnerability exists in the /json/upload endpoint of pyLoad. By manipulating the filename of an uploaded file, an attacker can traverse out of the intended upload directory, allowing them to write arbitrary files to any location on the system accessible to the pyLoad process. This may lead to: Remote Code Execution (RCE), local privilege escalation, system-wide compromise, persistence, and backdoors. This is fixed in version 0.5.0b3.dev90.
pyLoad vulnerable to remote code execution through js2py onCaptchaResult
pyload is an open-source Download Manager written in pure Python. An unsafe JavaScript evaluation vulnerability in pyLoad’s CAPTCHA processing code allows unauthenticated remote attackers to execute arbitrary code in the client browser and potentially the backend server. Exploitation requires no user interaction or authentication and can result in session hijacking, credential theft, and full system remote code execution. Commit 909e5c97885237530d1264cfceb5555870eb9546, the patch for the issue, is included in version 0.5.0b3.dev89.